Metathesis is generally thought of as the interchange of radicals between two compounds during a chemical reaction. There are several varieties of metathesis reactions, such as ring opening metathesis, acyclic diene metathesis, ring closing metathesis, and cross metathesis. These reactions, however, have had limited success with the metathesis of functionalized olefins.
Methods for the production of polyolefins with end-functionalized groups are typically multi-step processes that often create unwanted by-products and waste of reactants and energy.
R. T. Mathers and G. W. Coates, Chem. Commun., 2004, pp. 422-423 disclose examples of using cross-metathesis to functionalize polyolefins containing pendant vinyl groups to form polar-functionalized products with a graft-type structure.
C. Ornelas et al., J. Am. Chem. Soc. 2008, 130, pp. 1495-1506, and C. Ornelas et al., Angew. Chem. Int. Ed., 2005, 44, pp. 7399-7404 disclose examples of using cross metathesis to functionalize non-polymeric molecules containing vinyl groups.
For reviews of methods to form end-functionalized polyolefins, see: (a) S. B. Amin and T. J. Marks, Angew. Chem. Int. Ed., 2008, 47, pp. 2006-2025; (b) T. C. Chung, Prog. Polym. Sci., 2002, 27, pp. 39-85; (c) R. G. Lopez, F. D'Agosto, C. Boisson, Prog. Polym. Sci., 2007, 32, pp. 419-454.
U.S. Ser. No. 12/488,093, filed Jun. 19, 2009 discloses end functionalized polyolefins prepared from vinyl terminated polyolefins by cross metathesis.
Additional references of interest include U.S. Pat. No. 4,988,764 and U.S. Pat. No. 6,225,432.
Currently, most lubricant base stocks are derived from crude oil distillate fractions by processes such as hydrocracking, catalytic dewaxing and solvent dewaxing which adjust the size and degree of branching of the distillate fractions. However, owing to the high price of crude oil and the unstable nature of the oil supply worldwide, there is an increasingly strong incentive to produce lubricant base stocks from alternative sources.
Important alternative sources of hydrocarbons available in large supply in most modern refineries include norbornene and norbornadiene since these can be produced by the Diels-Alder reaction of cyclopentadiene with ethylene and acetylene, respectively. Cyclopentadiene is itself available in large quantities as a by-product of the steam cracking of naphtha and gas oils to produce ethylene and the distillation of coal tar. There is, therefore, significant interest in developing new uses for norbornene and norbornadiene.
For example, norbornene can be converted to polynorbornene by ring-opening metathesis polymerization (ROMP) using complex ruthenium catalysts, such as a Walker' catalyst:

The resultant polynorbornene is used mainly in the rubber industry and usually has a high glass transition temperature and high optical clarity.
In addition, Walker and his coworkers have produced block copolymers of norbornene and cyclooctene; see Macromolecules, 2009, 42, 599 to 605. Further, work by La and coworkers have shown that certain molybdenum alkylidenes catalyze chain transfer of polynorbornene with dienes and styrene, see J. Am. Chem. Soc., 1999, 121, 11603 to 11604. Olefins, such as 1-pentene are, however, reported to be unreactive for this chain termination.
A variation on ring-opening metathesis polymerization which has to date been the subject of only limited research is ring-open cross metathesis (ROCM). ROCM involves a tandem sequence in which a cycloolefin is opened and a second, acyclic olefin is then crossed onto the newly formed termini.
For example, U.S. Pat. No. 6,803,429 discloses that certain Group 8 metal alkylidene complexes substituted with N-heterocyclic carbine ligands catalyze the ring-opening cross-metathesis of cycloolefins with acyclic olefinic reactants, particularly α,β-unsaturated carbonyl compounds. The ROCM products are said to be mainly monomeric, dimeric or oligomeric species, rather than polymers.
Likewise, US 2008/0064891 discloses ring opening cross-metathesis reaction of cyclic olefins with seed oils and the like comprising contacting: (a) at least one olefinic substrate selected from (i) an unsaturated fatty acid, (ii) an unsaturated fatty alcohol, (iii) an esterification product of an unsaturated fatty acid with an alcohol, and (iv) an esterification product of a saturated fatty acid with an unsaturated alcohol, with (b) at least one cyclic olefin as a cross metathesis partner, in the presence of (c) a ruthenium alkylidene olefin metathesis catalyst, (d) under conditions effective to allow ring insertion cross metathesis whereby the cyclic olefin is simultaneously opened and inserted into the olefinic substrate.
Further WO98/40373 discloses ROCM on solid supports to isolate the olefin immobilized on the resin, preventing unwanted olefin polymerization.
EP 1 693 357 discloses a process for carrying out a ring opening cross-metathesis reaction between a liquid cyclic olefin and a gaseous acyclic olefin in a fixed bed system using Re2O7—B2O3/Al2O3 to produce 1,9-decadiene.
According to the present invention it has now been found that novel polymers of cyclic monomers and linear mono-olefins useful in the production of lubricant basestocks, among other things, can be produced by the ring-opening cross-metathesis of cyclic monomers (such as C5 based cyclic olefins) with linear mono-olefins (such as C2 to C20 linear mono-olefins) using alkene metathesis catalysts (such as asymmetric ruthenium alkylidene complexes). In a preferred embodiment, the instant invention provides process and catalyst systems which are effective for both ring-opening polymerizations with cyclic olefins (such as C5 based cyclic olefins) and cross-metathesis reactions with linear mono-olefins olefins in one reactor.
Polymers prepared by metathesis herein are of interest for use in a broad range of applications as lubricant, compatibilizers, tie-layer modifiers, surfactants, and surface modifiers, among other things. Further, hydrogenation of such leads to unique polymers that can be used in applications such as lubricants, compatibilizers, tie-layer modifiers, surfactants, and surface metathesis polymerization.